Why the powerful are more likely to cheat

Psychologists find a correlation between self-perception of power and a person's (un)willingness to remain faithful.

University of Rochester

Being a captain of industry, a politician, or a celebrity won’t automatically make you a cheat. But chances of infidelity are significantly higher among the more powerful, according to a new study published in Archives of Sexual Behavior.

Psychologists from Reichman University in Herzliya, Israel, and the US-based University of Rochester conducted a series of experiments and discovered that power dynamics play an important role in how people feel and behave when it comes to being faithful to their spouses or significant others.

Why? Prior research has established that feeling and being perceived as powerful can make people feel more confident and entitled—and likely to act more impulsively. Previous studies have shown that those who possess relatively greater degrees of power have more potential to influence, change, or control another person, or, conversely, to resist another person’s efforts to influence them.

The new study adds to the body of existing research by applying it specifically to intimate relationships, finding that those who feel more powerful are less dependent on others, think more highly of themselves, and are more confident that others find them desirable.

“In a romantic relationship, these power dynamics might lead the more powerful partner to think they bring more to the table than their less powerful partner,” says lead author Gurit Birnbaum, a professor of psychology at Reichman University. “The more powerful might see this as a sign that they have more options outside the relationship and are more desirable partners in general.”

Four tests of relationship power dynamics

The researchers conducted a series of four studies to test how perceptions of relationship power influence a person’s interest in alternative partners. They recruited participants who were in monogamous, heterosexual relationships of at least four months.

• In the first study, as a form of power manipulation, participants were asked to describe either a time they felt powerful vis-à-vis their current partner or a typical day in their relationship. Afterward they wrote a sexual fantasy about someone other than their partner.

• In the second study, following the same power manipulation, participants looked at photos of strangers and decided under time pressure which ones, if any, they would consider as potential partners.

• In the third study, participants described the power dynamics in their existing romantic relationship and rated their own perceived power and mate value compared to that of their partner. Next, participants were asked to complete a task with an attractive person, who was a study insider, and then rated their sexual desire for the insider.

• In the fourth study, both partners in a relationship reported separately each day for three weeks on their perceived relationship power, their perceived value as a partner, and any sexual activities—including sexual fantasies, flirting, or having sex—with someone other than their partner.

The destructive side of power

Across the four studies, the team found that perceptions of power within a relationship significantly predicted a person’s interest in other potential mates—including sexual fantasies, desires, and real-life interactions. That is, people who perceived themselves as having more power in their relationship were more interested in others as potential partners.

“Those with a higher sense of power may feel motivated to disregard their commitment to the relationship and act on desires for short-term flings or potentially other, more novel partners if the opportunity arises,” says coauthor Harry Reis, a psychology professor at the University of Rochester.

People who feel more powerful in their relationship tended to rate their value as a partner higher than their partner’s value, which could become destructive.

“When people feel powerful and believe they have more relationship options than their current partner, they might be more inclined to pay attention to other potentially promising alternatives,” says Reis. “The belief in having other options, like other possible partners, can weaken their commitment to their current relationship.”

 

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Journal

Archives of Sexual Behavior

DOI

10.1007/s10508-024-02997-0 

Method of Research

Experimental study

Subject of Research

People

Article Title

The Power to Flirt: Power within Romantic Relationships and Its Contribution to Expressions of Extradyadic Desire

 

Herodotus' theory on Armenian origins debunked by first whole-genome study

Peer-Reviewed Publication

Trinity College Dublin

Armenians, a population in Western Asia historically inhabiting the Armenian highlands, were long believed to be descendants of Phrygian settlers from the Balkans. This theory originated largely from the accounts of the Greek historian Herodotus, who observed that Armenians were armed in Phrygian fashion when serving in the Persian army. Linguists further supported this theory, suggesting that the Armenian language shares ties with the Thraco-Phrygian subgroup of Indo-European languages.

But the first whole-genome study is challenging this long-held belief, revealing no significant genetic link between Armenians and the populations in the Balkan region. The study compares newly generated modern Armenian genomes and published genetic data of ancient individuals from the Armenian highlands with both modern and ancient genomes from the Balkans. 

“For centuries, historical beliefs have shaped our understanding of the past, often leading us to accept theories as truth,” said Dr Anahit Hovhannisyan, Marie Curie Fellow in Trinity College Dublin’s School of Genetics and Microbiology, and first author of the just-published study in the American Journal of Human Genetics.

“However, with the availability of whole genome sequencing and the advancement of ancient DNA research, we can now question and reframe these long-held ideas, revealing a much more nuanced and scientifically grounded view of the history of human populations.”

The researchers behind the new study also disproved another belief – claims of an Assyrian ancestry for the Sasun, an Armenian population that inhabited the southern part of the Armenian highlands (modern-day southeastern Turkey). This connection had been referenced in many historical sources, including the Bible, in cuneiform texts, and local traditional stories. Instead, they found that the Sasun had experienced a significant contraction in size in the recent past, which sets them apart from other populations.

“While checking for genetic continuity in the Armenian highlands, we found a genetic input into the region from a source linked to Neolithic Levantine farmers at some point after the Early Bronze Age. In terms of timing and genetic ancestry, this aligns with previous findings in adjacent regions, thus allowing us to conclude that there was a large-scale post-Early Bronze Age movement across the Middle East. The questions of exactly where and when it came from, as well as what triggered such a widespread migration wave, remain unanswered and yet to be studied,” said Andrea Manica, Professor at the University of Cambridge, who is the last and co-senior author in the publication.

Researchers also shed light on the population structure and genetic variation of different Armenian groups, finding that populations from the eastern, western, and central parts of the Armenian highlands show a relatively high level of similarity. 

“This is the first study attempting to draw the genetic atlas of the Armenian highlands,” said Levon Yepiskoposyan, Professor at the Institute of Molecular Biology, NAS RA, and co-senior author of the publication.

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Journal

American Journal of Human Genetics

 

Key brain circuit for female sexual rejection uncovered

Champalimaud Centre for the Unknown

 

image: 

Example neuron in the anterior ventromedial hypothalamus (VMH, blue line). Using a technique called “uncaging”, researchers found that inhibitory signals near the centre of this neuron (yellow squares) were stronger during the fertile phase of the reproductive cycle. Reduced activity in these cells promotes mating behaviour.

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Credit: Nicolas Gutierrez-Castellanos, Lima Lab, Champalimaud Foundation

A team from the Champalimaud Foundation (CF) has pinpointed a critical neural circuit for sexual rejection, identifying a set of brain cells that play a crucial role in determining whether a female accepts or rejects mating attempts based on her reproductive cycle. Their findings, published today in Neuron, deepen our understanding of how the brain regulates social and reproductive behaviours.

Female mammals, such as rodents, accept mating attempts only during their fertile phase, and actively reject males outside this period. While the brain areas controlling sexual receptivity are well-studied, the mechanisms behind active rejection are less so.

“Sexual rejection isn’t just the absence of receptivity, it’s an active behaviour”, explains Susana Lima, senior author and head of the Neuroethology Lab at CF. “Females exhibit defensive actions like running away, kicking, or boxing the male. We wanted to understand how the brain switches between these two drastically different behavioural states”.

Central to their research is the ventromedial hypothalamus (VMH), an evolutionarily ancient brain region that controls social and sexual behaviour across species, including humans. “We suspected that the VMH might house a separate population of cells dedicated to rejection, based on previous low-resolution imaging experiments showing VMH activity during both acceptance and rejection of male advances”, says Lima.

The team focused on the anterior VMH, a less-explored area, particularly on cells responsive to the hormone progesterone, which fluctuates throughout the reproductive cycle. “These neurons are ideal for studying how the female brain toggles between acceptance and rejection during the cycle”, notes first author Nicolas Gutierrez-Castellanos.

No. Yes. It Depends.

“Understanding this flip gives us insight into how the brain integrates signals from the environment and the body to shape behaviour”, continues Gutierrez-Castellanos. “It’s a striking example of how the same stimulus—in this case, an eager male—can elicit completely opposite behaviours, depending on the female’s internal state”.

Through advanced techniques like fibre photometry—which tracks real-time brain activity by measuring calcium signals—researchers observed the behaviour of these progesterone-sensitive neurons in both receptive and non-receptive female mice during interactions with males. The results were striking: anterior VMH neurons became highly active in non-receptive females, correlating with defensive actions like kicking and boxing, but were far less active in receptive females.

“It appears that progesterone-responsive neurons in the anterior VMH act as gatekeepers for sexual rejection”, says co-first author Basma Husain. “When a female is outside her fertile window, these neurons become highly active, prompting rejection. But during fertility, their activity decreases, allowing mating to occur”.

The Brain’s Dual Control Knobs

How do these neurons switch on or off depending on fertility? To investigate, the team performed electrophysiology experiments, measuring the activity of progesterone-responsive neurons in brain slices. “We found that in non-receptive females, these neurons received more excitatory signals, making them more likely to be activated”, explains Gutierrez-Castellanos. “In receptive females, they received more inhibitory signals, reducing their likelihood of firing. It’s a testament to how adaptable and flexible neural connections in the hypothalamus—and the brain—can be”.

“The activity levels and excitation/inhibition balance of progesterone-responsive neurons in the anterior VMH strongly suggested their role in sexual rejection”, says Husain. “To confirm this, we used optogenetics to selectively activate these neurons with light”. Indeed, artificially stimulating them during the fertile phase induced rejection behaviours such as kicking and boxing. “It’s like flipping a switch—even though the females were fertile, they acted as if they weren’t”.

Conversely, silencing these neurons with a chemical drug in non-receptive females reduced rejection behaviours, though interestingly, it didn’t make them fully receptive—indicating that two distinct populations of neurons, one controlling rejection and the other receptivity, work in concert to produce the appropriate behaviour according to the female’s internal state.

“This setup gives the brain two ‘knobs’ to adjust”, Lima explains. “It’s a more efficient and robust way for the brain to balance these behaviours, ensuring mating occurs when conception is most likely, while minimising the risks and costs of mating, such as exposure to predators or diseases”.

Husain adds, “This dual-system likely adds flexibility to the brain’s regulation of sexual behaviour. Sex isn’t deterministic. Even during the receptive phase, a female might still reject males, so the ability to draw on both sets of neurons may allow for more nuanced and dynamic behaviours”.

Notably, these findings align with recent research showing that progesterone-responsive neurons in the posterior VMH, which drive sexual receptivity, undergo similar cycle-dependent changes, but in the opposite direction—active during the fertile phase and inactive outside it.

“The VMH exists in humans and likely plays similar roles”, notes Lima. “Recent studies in mouse models have shown that the VMH changes in pathological conditions like polycystic ovarian syndrome. Additionally, socially isolating female mice during development may lead to reduced sexual receptivity, with alterations in the same brain area, underscoring the VMH’s clinical relevance”.

“We’re just beginning to scratch the surface of how the brain’s internal wiring orchestrates social behaviour”, concludes Lima. “There’s much more to learn, but these findings bring us a step closer to understanding how neural mechanisms and internal states drive complex social interactions, from sexual behaviour to aggression and beyond”.

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Journal

Neuron

Method of Research

Experimental study

Subject of Research

Animals

Article Title

A hypothalamic node for the cyclical control of female sexual rejection

Article Publication Date

25-Nov-2024

 

Scientists find why tamoxifen works better for some people

American Society for Microbiology

Highlights:

• Tamoxifen is a common and important treatment to prevent breast cancer from recurring.
• A new study shows that variation in a patient’s gut microbiome can impact how effective the treatment is.

Washington, D.C. — Nov. 25, 2024 — A new study has shown that variation in the microbiota of the human gut impacts the pharmacokinetics of tamoxifen and thus the effectiveness of the drug. The finding, published in the journal mBio of the American Society for Microbiology, suggests that in the future, doctors may use a simple test on a patient’s stool to check for certain bacteria in the gut that might help predict whether tamoxifen will work for them.

“The key takeaway from this study is that while tamoxifen is a common and important treatment for preventing breast cancer recurrence, nearly 50% of patients don’t respond well to it,” said lead study author Yasmine Alam, a Ph.D. candidate in the Department of Biological Chemistry, University of California Irvine. “Since tamoxifen is taken orally and passes through the gut, this difference in how patients respond may be linked to the gut microbiome—the trillions of bacteria in our intestines, which vary greatly from person to person. Our study aims to better understand how these gut bacteria influence the way tamoxifen is absorbed, broken down and recycled in the body, with the goal of improving treatment outcomes for breast cancer patients.”

In the new study, the researchers set out to define the role that gut microbes play in how tamoxifen is processed (i.e., absorption, distribution, metabolism and excretion), given its significant variable efficacy across patients. The researchers provided tamoxifen to mice that had no gut microbiome and to mice with a human microbiome (introduced to the mice by a human fecal sample). They found that mice with gut bacteria had higher amounts of tamoxifen in their bloodstream. The scientists then went on to explore what part of the gut microbiome was responsible for controlling the level of drug in the bloodstream. By examining the fecal samples from people, they linked a specific enzyme in bacteria, beta-glucuronidase, as a key factor that allows the drug to enter the bloodstream.

When a person swallows a tamoxifen pill, it passes through their stomach and into their intestines, where it is absorbed into the bloodstream. Once in the blood, tamoxifen makes its way to the liver, where the drug is changed into a form that is more effective at fighting breast cancer. However, a sugar molecule can sometimes get attached to it, which signals the body to dump the cancer-fighting form of the drug back into the intestine, instead of into the bloodstream where it can then move to the parts of the body where it needs to fight the cancer. This drug can only get out of the intestine by taking the sugar off the molecule—and the researchers found that beta-glucuronidase in gut bacteria can eat the sugar off the drug so it can go on to fight breast cancer.

“Specifically, we found that certain enzymes produced by gut bacteria, called β-glucuronidase, play a role in how tamoxifen is broken down. These enzymes help recycle tamoxifen back into the bloodstream, which can make the drug more effective,” Alam said. “We discovered that a particular type of bacteria, Bacteroides fragilis, was strongly linked to the ability of these enzymes to affect tamoxifen levels in the blood in a positive way. This suggests that the gut microbiome plays an important role in how tamoxifen works in the body.”

The long-term goal of the study is to pave the way for more tailored and effective therapeutic interventions in the prevention of breast cancer recurrence.

The study was led by Elizabeth Bess, Ph.D., assistant professor in the department of chemistry at UC Irvine, and Cholsoon Jang, Ph.D., assistant professor in the department of biological chemistry at UC Irvine.

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The American Society for Microbiology is one of the largest professional societies dedicated to the life sciences and is composed of over 32,000 scientists and health practitioners. ASM's mission is to promote and advance the microbial sciences.

ASM advances the microbial sciences through conferences, publications, certifications, educational opportunities and advocacy efforts. It enhances laboratory capacity around the globe through training and resources. It provides a network for scientists in academia, industry and clinical settings. Additionally, ASM promotes a deeper understanding of the microbial sciences to diverse audiences.

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Journal

mBio

 

New study reveals the explosive secret of the squirting cucumber

University of Oxford

 

video: 

Caption:High speed colour video showing the ejection of seeds by the squirting cucumber (Ecballium elaterium). The video is captured at 10,000 fps, and so is slowed down 400 times. Credit: Dominic Vella

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Credit: Dominic Vella

A team led by the University of Oxford has solved a mystery that has intrigued scientists for centuries: how does the squirting cucumber squirt? The findings, achieved through a combination of experiments, high-speed videography, image analysis, and advanced mathematical modelling, have been published today (25 November) in The Proceedings of the National Academy of Sciences (PNAS).

The squirting cucumber (Ecballium elaterium, from the Greek ‘ekballein,’ meaning to throw out) is named for the ballistic method the species uses to disperse its seeds. When ripe, the ovoid-shaped fruits detach from the stem and eject the seeds explosively in a high-pressure jet of mucilage. This projectile launch – lasting just 30 milliseconds- causes the seeds to reach speeds of around 20 metres per second, and land at distances up to 250 times the length of the fruit (around 10 m).

Until now, the exact mechanism of the squirting cucumber’s seed dispersal - and how this affects its reproductive success - remained poorly understood. In the new study, researchers from the University of Oxford and the University of Manchester conducted a variety of experiments on Ecballium specimens grown at the University of Oxford Botanic Garden.

This included filming the seed dispersal using a high-speed camera (capturing up to 8600 frames per second), measuring fruit and stem volume before and after dispersal, performing indentation tests and CT scans of an intact cucumber, and monitoring the fruit with time-lapse photography in the days leading up to launch. They then developed a suite of mathematical models to describe the mechanics of the pressurized fruit, the stem, and the ballistic trajectories of the seeds.

Using this combined approach, the team elucidated the key components of the plant’s dispersal strategy:

1. A pressurised system: In the weeks leading up to seed dispersal, the fruits become highly pressurised due to a build-up of mucilaginous fluid.
2. Fluid redistribution: In the days before dispersal, some of this fluid is redistributed from fruit to stem, making the stem longer, thicker, and stiffer. This causes the fruit to rotate from being nearly vertical to an angle close to 45°, a key element needed for successful seed launch.
3. A rapid recoil: In the first hundreds of microseconds of ejection, the tip of the stem recoils away from the fruit, causing the fruit to counter-rotate in the opposite direction.
4. Variable launch: Due to the components above, the seeds are ejected with an exit speed and launch angle that depend on their sequence: with subsequent seeds, the exit speed decreases (because the pressure of the now emptying fruit capsule decreases) while the launch angle increases (due to the fruit’s rotation). This causes the initial seeds to reach the furthest distance, with subsequent seeds landing closer. As multiple fruits are distributed around the centre of the plant, the overall result is a wide and nearly uniform distribution of seeds covering a ring-shaped area at a distance of between 2 and 10 m from the mother plant.

Together, these components make up a sophisticated seed dispersal system. In particular, the redistribution of fluid from the fruit back into the stem is thought to be unique within the plant kingdom.

Using the mathematical model, the researchers explored the consequences of artificially altering different parameters. This revealed that the seed projection method of the squirting cucumber has been fine-tuned to ensure near-optimal dispersal and the success of the plant over generations.

For instance, making the stem thicker and stiffer resulted in the seeds being launched almost horizontally, since the fruit would rotate less during discharge. This would cause the seeds to be distributed over a narrower area, with fewer likely to survive.

Meanwhile, reducing the amount of fluid redistributed from the fruit to the stem resulted in an over-pressurised fruit, causing the seed to be ejected at higher speeds but at a nearly vertical launch angle. Consequently, the seeds would not be dispersed far enough away from the parent plant, and again, few would survive.

Author Dr Chris Thorogood (Deputy Director and Head of Science at Oxford Botanic Garden) said: ‘For centuries people have asked how and why this extraordinary plant sends its seeds into the world in such a violent way. Now, as a team of biologists and mathematicians, we’ve finally begun to unravel this great botanical enigma.’

Co-author Dr Derek Moulton (Professor of Applied Mathematics at the Oxford Mathematical Institute) said: `The first time we inspected this plant in the Botanic Garden, the seed launch was so fast that we weren’t sure that it had actually happened. It was very exciting to dig in and uncover the mechanism of this unique plant.’

According to co-author Dr Finn Box, (Royal Society University Research Fellow, University of Manchester), ‘This research offers potential applications in bio-inspired engineering and material science, particularly on-demand drug delivery systems, for instance microcapsules that eject nanoparticles where precise control of rapid, directional release is crucial.’

Ecballium elaterium (pronounced: eck-ball-ee-uhm elaht-eh-ree-uhm) is a member of the gourd family (Cucurbitaceae) which also includes melon, pumpkin, squash, and courgette. The species is native to the Mediterranean, where – thanks to its effective seed-dispersal strategy- it is often regarded as a weed. The plant was described by the ancient Greeks and Romans: naturalist Pliny the Elder (AD 23/24 – AD 79) said ‘Unless, to prepare it, the cucumber be cut open before it is ripe, the seed spurts out, even endangering the eyes.’

Notes to editors:

For media requests and interviews, contact Caroline Wood: caroline.wood@admin.ox.ac.uk

Images and video relating to the study are available for use in articles here: https://drive.google.com/drive/folders/1R3AN88zAhu0xMXzYqGUkYkXLBz0noCHw?usp=drive_link These images are for editorial purposes relating to this press release only and MUST be credited (see captions file in folder). They MUST NOT be sold on to third parties.

The study ‘Uncovering the mechanical secrets of the squirting cucumber’ will be published in The Proceedings of the National Academy of Sciences (PNAS) from 20:00 GMT / 15:00 ET Monday 25 November 2024 at https://www.pnas.org/cgi/doi/10.1073/pnas.2410420121

To view a copy of the paper before this under embargo, access the PNAS area of EurekAlert here: https://www.eurekalert.org/news-releases/1065569 (this requires registration to EurekAlert).

About the University of Oxford Botanic Garden and Arboretum

Oxford Botanic Garden is the UK’s oldest botanic garden, founded in 1621. The Garden was first established as a physic garden for the cultivation of medicinal plants, and still occupies a unique position in terms of its history and academic location to this day. It was the birthplace of botanical science in the UK and has been a centre for plant research since the 1600s.

Oxford Botanic Garden’s mission is to share the scientific wonder of plants and the importance of plants with the world. It holds a collection of about 5,000 different types of plant, together with its sister site, Harcourt Arboretum. Some of these species exist nowhere else and are of international conservation importance.

CT scan, squirting cucumber. [VIDEO] | 

The squirting cucumber, Ecballium elaterium. Credit: Derek Moulton

The fruit of the squirting cucumber, Ecballium elaterium. Credit: Chris Thorogood

A still showing the jet ejected from a squirting cucumber, which carries its seeds distances of up to 10m away from the mother plant. Credit: Dominic Vella

Credit

Journal

Proceedings of the National Academy of Sciences

DOI

10.1073/pnas.2410420121 

Article Title

Uncovering the mechanical secrets of the squirting cucumber

Article Publication Date

25-Nov-2024

 

H.E.S.S. collaboration detects the most energetic cosmic-ray electrons and positrons ever observed

CNRS

 

image: 

Visualisation of the H.E.S.S. telescope array capturing the showers of particles produced by high-energy cosmic electrons and positrons, as well as gamma rays.

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Credit: © MPIK/H.E.S.S. Collaboration

The Universe teems with extreme environments, ranging from the very coldest temperatures to the highest energy sources possible. As a consequence, extreme objects such as supernova remnants, pulsars and active galactic nuclei are capable of emitting charged particles and gamma rays with incredibly high energies, so high that they exceed the energy produced by the nuclear fusion in stars by several orders of magnitude.

The gamma rays detected on Earth tell us a great deal about these sources, since they travel through space undisturbed. However, in the case of charged particles, also known as cosmic rays, things are more complicated because they are constantly buffeted by the magnetic fields present everywhere in the Universe, and impact the Earth isotropically, in other words from all directions. What's more, these charged particles lose some of their energy along the way, when they interact with light and magnetic fields. These energy losses are especially significant for the most energetic electrons and positrons, known as cosmic-ray electrons (CRe), whose energy exceeds one teraelectronvolt (TeV) (i.e. 1000 billion times greater than that of visible light)1. It is therefore impossible to determine the point of origin of such charged particles in space, although their detection on Earth is a clear indicator that there are powerful cosmic-ray particle accelerators in its vicinity.

However, detecting electrons and positrons with energies of several teraelectronvolts is particularly challenging. Space-based instruments, with detection areas of around one square metre, are unable to capture sufficient numbers of such particles, which become increasingly rare the higher their energy. Ground-based instruments on the other hand, which indirectly detect the arrival of cosmic rays via the showers of particles they produce in the Earth's atmosphere, are faced with the challenge of differentiating the showers triggered by cosmic-ray electrons (or positrons) from the much more frequent showers produced by the impact of the heavier cosmic-ray protons and nuclei. The H.E.S.S. Observatory2 located in Namibia uses five large telescopes to capture and record the faint Cherenkov radiation produced by the heavily charged particles and photons that enter the Earth's atmosphere, producing a shower of particles in their wake. Although the Observatory’s main purpose is to detect and select gamma rays in order to investigate their sources, the data can also be used to search for cosmic-ray electrons.

In the most extensive analysis ever carried out, H.E.S.S. collaboration scientists have now obtained new information about the origin of these particles. The astrophysicists did this by combing through the huge data set collected over the course of a decade by the four 12-metre telescopes, applying new, more powerful selection algorithms capable of extracting the CRe from the background noise with unprecedented efficiency. This resulted in an unrivalled set of statistical data for the analysis of cosmic-ray electrons. More specifically, the H.E.S.S. researchers were able to obtain for the first time data about CRe in the highest energy ranges, all the way up to 40 TeV. This enabled them to identify a surprisingly sharp break in the energy distribution of the cosmic-ray electrons.

“This is an important result, as we can conclude that the measured CRe most likely originate from very few sources in the vicinity of our own solar system, up to a maximum of a few 1000 light years away, a very small distance compared to the size of our Galaxy”, explains Kathrin Egberts, from the University of Potsdam, one of the corresponding authors of the study.

“We were able to put severe constrains on the origin of these cosmic electrons with our detailed analysis for the first time”, adds Prof. Hofmann from the Max-Planck-Institut für Kernphysik, co-author of the study. “The very low fluxes at larger TeV limit the possibilities of space-based missions to compete with this measurement. Thereby, our measurement does not only provide data in a crucial and previously unexplored energy range, impacting our understanding of the local neighbourhood, but it is also likely to remain a benchmark for the coming years”, Mathieu de Naurois, CNRS Researcher from the Laboratoire Leprince-Ringuet, adds.

 

Caption

Artist's impression of a pulsar with its powerful magnetic field rotating around it. The clouds of charged particles moving along the field lines emit gamma rays that are focused by the magnetic fields, rather like the beams of light from a lighthouse. In these magnetic fields, pairs of positrons and electrons are created and accelerated, making pulsars potential sources of high-energy cosmic electrons and positrons.

Credit

©NASA/Goddard Space Flight Center Conceptual Image Lab

Footnotes :

1. 1 TeV = 1012 electronvolts.
2. High-energy gamma rays can  be observed from the ground only because of a very specific phenomenon. When a gamma ray enters the atmosphere it collides with its atoms and molecules, producing new particles that sweep towards the ground rather like an avalanche. The particles emit flashes lasting mere billionths of a second (Cherenkov radiation), which can be observed using large, specially equipped ground-based telescopes. The H.E.S.S. Observatory, located in the Khomas Highlands of Namibia at an altitude of 1835 m, officially began operation in 2002. It comprises an array of five telescopes. Four telescopes with mirrors 12 m in diameter are located at the corners of a square, with another 28 m telescope at the centre. This makes it possible to detect cosmic gamma rays ranging from a few tens of gigaelectronvolts (GeV, 109 electronvolts) to a few tens of teraelectronvolts (TeV, 1012 electronvolts). By comparison, photons of visible light have an energy of two to three electronvolts. H.E.S.S. is currently the only instrument observing the southern sky in high-energy gamma-ray light. It is also the largest and most sensitive telescope system of its kind.

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Journal

Physical Review Letters

Article Title

High-Statistics Measurement of the Cosmic-Ray Electron Spectrum with H.E.S.S.

Article Publication Date

18-Nov-2024

 

Focaccia: a Neolithic culinary tradition dating back 9,000 years ago

Universitat Autonoma de Barcelona

 

image: 

‘Focaccia’ with animal fat experimentally baked in a replica husking tray inside a domed oven. Author: Sergio Taranto

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Credit: Author: Sergio Taranto

A study led by researchers from the UAB and the University La Sapienza in Rome indicates that during the Late Neolithic, between 7000 and 5000 BCE, the fully agricultural communities in the Fertile Crescent region of the Near East, developed a complex culinary tradition that included the baking of large loaves of bread and “focaccias” with different flavours on special trays known to archaeologists as husking trays.

The study was published in the journal Scientific Reports (Nature Portfolio) and also involved staff from the Milà i Fontanals Institution (IMF-CSIC) and the University of Lyon (France).

The husking trays were containers with a large oval base and low walls, made of coarse clay. They differed from common trays due to their internal surface, marked with rough impressions or incisions arranged repetitively and regularly. Previous experiments using replicas of these trays and cooking structures similar to those found at archaeological sites from the studied period had already allowed researchers to hypothesize their function. These investigations suggested that large loaves made with water and flour might have been baked on these trays, placed in domed ovens for about 2 hours at an initial temperature of 420°C. The grooves on the internal surface would have facilitated the removal of the bread once baked. Moreover, the large size of the loaves, approximately 3 kg, suggested they were likely intended for communal consumption.

The research team analyzed ceramic fragments of husking trays from between 6400 and 5900 BCE to identify their use as specialized containers for baking cereal-based doughs and whether these doughs could have been seasoned with products such as animal fat or vegetable oil. The analyzed remains come from the archaeological sites of Mezraa Teleilat, Akarçay Tepe, and Tell Sabi Abyad, located in the area between Syria and Turkey. The analyses were carried out at the Universities of Istanbul and the Koç (Turkey).

The study, based on various types of analyses from an integrated perspective, provides clear evidence regarding both the uses of these artifacts and the nature of the foods processed in them. In particular, the analysis of phytoliths (silica residues from plants) suggests that cereals such as wheat (Triticum sp.) or barley (Hordeum sp.), reduced to flour, were processed in these trays. Furthermore, the analysis of organic residues indicates that some of the trays were used to cook foods containing animal-derived ingredients, such as animal fat, and in one case, plant-based seasonings. The degradation state of the residues suggests that, in at least two cases, the trays reached temperatures compatible with those experimentally verified for baking dough in domed ovens. Finally, the use-alterations analysis of the ceramic surface allowed the identification of use-wear specifically associated with bread residues and others linked to seasoned focaccia residues.

“Our study offers a vivid picture of communities using the cereals they cultivated to prepare breads and ‘focaccias’ enriched with various ingredients and consumed in groups,” explains Sergio Taranto, lead author of the study, part of a doctoral thesis carried out at the UAB and La Sapienza. “The use of the husking trays we identified leads us to consider that this Late Neolithic culinary tradition developed over approximately six centuries and was practiced in a wide area of the Near East”, the researcher concludes.

Researchers from the UAB's Prehistoric Archaeology of the Near East Research Group (SAPPO), Adrià Breu, Anna Bach, and Miquel Molist, are also authors of the study.

‘Focaccia’ seasoned with animal fat baked in an experimental replica husking tray. Author: Sergio Taranto

Journal

Scientific Reports

DOI

10.1038/s41598-024-78019-9 

Method of Research

Experimental study

Subject of Research

Not applicable

Article Title

Unveiling the culinary tradition of ‘focaccia’ in Late Neolithic Mesopotamia by way of the integration of use-wear, phytolith & organic-residue analyses

Article Publication Date

25-Nov-2024